US astronaut Mike Hopkins, 45, took the astounding image of himself while performing repairs on the ISS during the second of two spacewalks spread over a four-day period.
The selfie shows the beautiful blue of Earth and Hopkins' colleague Rick Mastracchio in the reflection on his helmet.
"Wow...can't believe that is me yesterday. Wish I could find the words to describe the experience, truly amazing," Hopkins tweeted after the spacewalk.
On December 24, Hopkins, Expedition 38 Flight Engineer, participated in the second of two US spacewalks, which were designed to allow the crew to change out a faulty water pump on the exterior of the Earth-orbiting station, NASA said on instagram.
He was joined on both spacewalks by NASA astronaut Mastracchio, whose image appeared in Hopkins' helmet visor.
The pump module controls the flow of ammonia through cooling loops and radiators outside the space station, and, combined with water-based cooling loops inside the station, removes excess heat into the vacuum of space.